- Preparation method of clopidogrel hydrogen sulfate intermediate
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The present invention relates to a preparation method of a clopidogrel hydrogen sulfate intermediate. (+)-2-chlorophenylglycine methyl ester and alpha-thiopheneethanol p-toluenesulfonate are adopted as raw materials, a reaction solvent and an acid-binding agent are added for a condensation reaction, the condensation reaction process is divided into a first stage and a second stage, and when 60-95% of the condensation reaction is completed, first-stage reaction is completed; after the first-stage reaction is completed, firstly part of the reaction solvent is removed, and then second-stage reaction is carried out; and after the second-stage reaction is completed, a target product is obtained, namely the clopidogrel hydrogen sulfate intermediate. After the first-stage reaction is completed, part of the reaction solvent is removed firstly, and then the second-stage reaction is continued, so that the concentration of the reaction material can be increased in the later stage of the condensation reaction, the use amount of the reaction solvent is reduced, and racemization and side reaction in the reaction process are effectively inhibited, thereby improving the chiral purity of the product, increasing the yield, reducing the use of auxiliary materials greatly, and reducing the production cost.
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Paragraph 0032
(2021/05/15)
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- Preparation method of sulfonic clopidogrel impurity
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The invention discloses a preparation method of a sulfonic clopidogrel impurity. The preparation method comprises the following steps: reacting thiophene-2-ethanol with toluenesulfonyl chloride to generate p-toluenesulfonic acid-2-thienylethyl ester; carrying out esterification on o-chlorophenylglycine and methanol to generate o-chlorophenylglycine methyl ester; resolving the o-chlorophenylglycinemethyl ester by using L(+) tartaric acid; converting into free S-(+)-o-chlorophenylglycine methyl ester in dichloromethane; carrying out a condensation reaction on the p-toluenesulfonic acid-2-thienylethyl ester and the S-(+)-o-chlorophenylglycine methyl ester under an alkaline condition; acidifying the obtained product to generate (S)-2-(2-thienylethylamino)(2-chlorphenyl)methyl acetate, carrying out a condensation reaction on the (S)-2-(2-thienylethylamino)(2-chlorphenyl)methyl acetate and formaldehyde to obtain clopidogrel, and carrying out a reaction on the clopidogrel and chlorosulfonicacid to generate sulfonic clopidogrel impurity. The preparation method of the sulfonic clopidogrel impurity has the advantages of mild reaction conditions, accessible raw materials, low cost and highyield and purity.
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Paragraph 0012; 0024-0026
(2020/08/02)
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- Structure-Odor Correlations in Homologous Series of Mercapto Furans and Mercapto Thiophenes Synthesized by Changing the Structural Motifs of the Key Coffee Odorant Furan-2-ylmethanethiol
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Furan-2-ylmethanethiol (2-furfurylthiol; 2-FFT, 1) is long-known as a key odorant in roast and ground coffee and was also previously identified in a wide range of thermally treated foods such as meat, bread, and roasted sesame seeds. Its unique coffee-like odor quality elicited at very low concentrations, and the fact that only a very few compounds showing a similar structure have previously been described in foods make 1 a suitable candidate for structure-odor activity studies. To gain insight into the structural features needed to evoke a coffee-like odor at low concentrations, 46 heterocyclic mercaptans and thio ethers were synthesized, 32 of them for the first time, and their odor qualities and odor thresholds were determined. A movement of the mercapto group to the 3-position kept the coffee-like aroma but led to an increase in odor threshold. A separation of the thiol group from the furan ring by an elongation of the carbon side chain caused a loss of the coffee-like odor and also led to an increase in odor thresholds, especially for ω-(furan-2-yl)alkane-1-thiols with six or seven carbon atoms in the side chain. A displacement of the furan ring by a thiophene ring had no significant influence on the odor properties of most of the compounds studied, but the newly synthesized longer-chain 1-(furan-2-yl)- and 1-(thiophene-2-yl)alkane-1-thiols elicited interesting passion fruit-like scents. In total, only 4 out of the 46 compounds also showed a coffee-like odor quality like 1, but none showed a lower odor threshold. Besides the odor attributes, also retention indices, mass spectra, and NMR data of the synthesized compounds were elaborated, which are helpful in possible future identification of these compounds in trace levels in foods or other materials.
- Schoenauer, Sebastian,Schieberle, Peter
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p. 4189 - 4199
(2018/05/01)
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- The clopidogrel hydrogen sulfate synthesis method (by machine translation)
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The invention discloses a clopidogrel hydrogen sulfate synthesis method, comprises the following steps: S1, 2 - (2 - thiophene) ethanol tosylates synthetic, S2, (+) - O-chlorobenzene glycine methyl brown oil of synthetic, S3, (S)- 2 - (2 - thiophene ethylamine) (2 - chlorophenyl) acetic acid methyl ester hydrochloride of synthetic, S4, the finished synthetic; the invention with conventional clopidogrel hydrogen sulfate existing synthesis method, the processing operation is more convenient, after treatment is simple, and is suitable for commercial production; high yield, few by-products, impurity removal easier; simple and easy to obtain, the cost is cheap. (by machine translation)
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Paragraph 0006; 0008
(2018/11/22)
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- Method for preparing D-(+)-alpha-(2-thiopheneethylamino)-alpha-(2-chlorophenyl)methyl acetate hydrochloride
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The invention provides a novel method for preparing D-(+)-alpha-(2-thiopheneethylamino)-alpha-(2-chlorophenyl)methyl acetate hydrochloride, aiming at solving the technical problems of a traditional synthesis technology of the D-(+)-alpha-(2-thiopheneethylamino)-alpha-(2-chlorophenyl)methyl acetate hydrochloride that the technology is complicated, the cost is high and the yield is low. The method comprises the following steps: 1) preparing 2-bromothiophene; 2) preparing 2-thiopheneethanol; 3) preparing 2-thiopheneethanol p-toluenesulfonate; 4) preparing L-(+)-o-chlorophenylglycine methyl esterL-tartrate; 5) preparing the D-(+)-alpha-(2-thiopheneethylamino)-alpha-(2-chlorophenyl)methyl acetate hydrochloride. The preparation method provided by the invention is low in cost, high in yield andhigh in safety and is suitable for industrial production.
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Paragraph 0009; 0058; 0064; 0067; 0076; 0083; 0094; 0103
(2018/12/14)
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- Synthetic method of p-toluene sulfonic acid-2-thiophene ethyl ester
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The invention relates to a synthetic method of p-toluene sulfonic acid-2-thiophene ethyl ester. According to the synthetic method, the p-toluene sulfonic acid-2-thiophene ethyl ester is synthesized by using 2-thiopheneethanol and p-toluene sulfonic acid as raw materials and using ferric nitrate as a catalyst through a one-step reaction. The invention provides a new method for synthesizing the p-toluene sulfonic acid-2-thiophene ethyl ester. The method has the characteristics of low cost, environmental-friendliness and simple process, and has industrial application value.
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Paragraph 0011; 0012
(2017/07/22)
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- Synthesis method of 4,5,6,7-tetrahydrothieno[3,2-c]pyridine hydrochloride
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The invention relates to a synthesis method of 4,5,6,7-tetrahydrothieno[3,2-c]pyridine hydrochloride. The method comprises the following steps: synthesizing 2-(2-thienyl)ethyl p-toluenesulfonate from 2-thiopheneethanol and paratoluensulfonyl chloride, further reacting the 2-(2-thienyl)ethyl p-toluenesulfonate with formamide to synthesize N-2-thienylethylformamide, carrying out cyclization on the N-2-thienylethylformamide under the action of trifluoroacetic acid to produce 6,7-dihydrothieno[3,2-c]pyridine, reducing the 6,7-dihydrothieno[3,2-c]pyridine with sodium borohydride, and carrying out salification to obtain the 4,5,6,7-tetrahydrothieno[3,2-c]pyridine hydrochloride. The invention provides a novel method for synthesizing the 4,5,6,7-tetrahydrothieno[3,2-c]pyridine hydrochloride. The method has the characteristics of low cost, low toxicity and simple technique, and has industrialized application prospects.
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Paragraph 0016
(2017/09/02)
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- A compound clopidogrel hydrogensulfate method for the preparation of
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The invention relates to a preparation method of clopidogrel disulfate. The preparation method comprises the following steps of step one. carrying out esterification reaction, namely preparing (+/-) DL-2-Chlorophenylglycine methyl ester; step two. carrying out splitting reaction, namely preparing (+) DL-2-Chlorophenylglycine methyl ester; step three. carrying out activating reaction, namely preparing alpha-thiophene ethanol p-toluenesulfonates; step four. carrying out substitution reaction, namely preparing (+) alpha-(2-thiophene ethylamino)-2-(2-chlorobenzene) methyl acetate hydrochloride; step five. carrying out ring closing reaction, namely preparing clopidogrel; and step six. carrying out salt-forming reaction, namely preparing the clopidogrel disulfate. The preparation method has the advantages that the preparation technology is optimized and improved, reaction conditions are mild, the splitting and the racemization are truly and synchronously carried out, and an obtained crude product has high specific rotation; a catalyst is used in the substitution reaction, so that the reaction time is shortened; the ring closing reaction is carried out at 40 DEG C under the condition of avoiding light, so that the purity of the product is relatively high; and the period of the whole synthetic route is shortened, the aftertreatment operation is simple, and therefore, the preparation method is suitable for mass production.
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Paragraph 0094-0096
(2017/01/26)
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- A 1,2-bis (2-thienyl) ethane method for the synthesis of
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The invention relates to a synthesis method of 1,2-di(2-thienyl)ethane, and particularly relates to a synthesis method of 1,2-di(2-thienyl)ethane by firstly converting 2-penphene as a raw material into thienyl borane, then reacting with p-toluene sulfonate-2-(2-thienyl)ethyl to generate 1,2--di(2-thienyl)ethane. The 1,2-di(2-thienyl)ethane is synthesized by the following steps: by taking 2-penphene as a raw material, firstly converting into thienyl borane, then reacting with p-toluene sulfonate-2-(2-thienyl)ethyl to generate 1,2--di(2-thienyl)ethane. The invention provides a new method for synthesizing 1,2-di(2-thienyl)ethane, and the synthesis method has the characteristics of being mild in reaction conditions, short in reaction route, and high in reaction yield.
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Paragraph 0015; 0016
(2017/02/09)
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- Method for synthesizing ticlopidine hydrochloride
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The invention provides a method for synthesizing ticlopidine hydrochloride. The method comprises the following steps: by using thiopheneethanol as a raw material, under the action of an acid binding agent, firstly, performing a reaction on the thiopheneethanol and paratoluensulfonyl chloride to carry out protection and activation on hydroxy; performing a condensation reaction with chlorobenzylamine; then under an acid condition, performing a ring closing reaction with 1,3-dioxolane to obtain the ticlopidine hydrochloride. The method is mild in reaction condition, low in production cost, high in product yield and high in quality, and is convenient for industrial production.
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Paragraph 0017
(2016/10/17)
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- Novel preparation method for ticlopidine hydrochloride
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The invention provides a novel preparation method for ticlopidine hydrochloride. The method comprises the following steps: with thiopheneethanol as a raw material, reacting thiopheneethanol with p-toluene sulfonyl chloride under the action of an acid binding agent so as to protect and activate a hydroxyl group; then subjecting a reaction product obtained in the previous step and o-chlorobenzylamine to a condensation reaction; and carrying out a ring closure reaction on a condensation reaction product and 1,3-dioxolane so as to obtain ticlopidine hydrochloride. The novel preparation method has the advantages of mild reaction conditions, low production cost, high product yield, good product quality and easy realization of industrial production.
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Paragraph 0017
(2016/10/17)
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- Method for synthesizing ticlopidine hydrochloride
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The invention provides a method for synthesizing ticlopidine hydrochloride. The method comprises the following steps of taking thiopheneethanol as a raw material, and protecting and activating hydroxyl by means of reacting the thiopheneethanol with paratoluensulfonyl chloride under the action of an acid-binding agent; then performing a condensation reaction with o-chlorobenzylamine; performing a ring closing reaction with 1,3-dioxolane under an acidic condition so as to obtain the ticlopidine hydrochloride. The method provided by the invention has the advantages of mild reaction condition, low production cost, high product yield, good quality and convenience for industrialized production.
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Paragraph 0018
(2016/10/31)
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- Method for preparing ticlopidine hydrochloride
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The invention provides a method for preparing ticlopidine hydrochloride, which comprises the following steps: reacting thienyl ethanol used as a raw material with paratoluensulfonyl chloride under the action of an acid-binding agent to protect and activate the hydroxy group; carrying out condensation reaction with ortho-chlorobenzylamine; and carrying out cyclization reaction with 1,3-dioxolane under acidic conditions to obtain the ticlopidine hydrochloride. The method has the advantages of mild reaction conditions, low production cost, high product yield and good product quality, and is convenient for industrial production.
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Paragraph 0015; 0017
(2016/12/16)
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- Preparation method of ticlopidine hydrochloride
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The invention provides a preparation method of ticlopidine hydrochloride. The preparation method comprises the following steps: reacting thiophene ethanol as a raw material with paratoluensulfonyl chloride at first under the action of an acid-binding agent so as to protect and activate hydroxyl radicals; then performing condensation reaction with o-chlorobenzylamine; and then under an acidic condition, performing ring-closing reaction with 1,3-dioxolane to obtain ticlopidine hydrochloride. The preparation method is mild in reaction condition, low in production cost, high in product yield and good in product quality, and can conveniently realize industrial production.
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Paragraph 0018
(2017/03/25)
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- Pd/C as a catalyst for completely regioselective c=h functionalization of thiophenes under mild conditions
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The completely C3-selective arylation of thiophenes and benzo[b]thiophenes was achieved by using Pd/C as a heterogeneous catalyst without ligands or additives under mild reaction conditions. The practicability of this transformation is demonstrated by notable functional group tolerance and the insensitivity of the reaction to H2O and air. This method is also applicable to nitrogen- and oxygen-containing heterocycles, yielding the corresponding C2-arylated products. Three-phase tests along with Hg-poisoning and hot-filtration tests suggest that the catalytically active species is heterogeneous in nature. I+ can do better! Pd/C can be used without ligands or additives to catalyze the completely C3-selective arylation of diversely substituted thiophenes and benzo[b]thiophenes under mild reaction conditions. The physical nature of the catalytic species was investigated and the mechanism was studied. Relative rate data generated in a "robustness screen" were used to design a complex substrate that undergoes highly chemoselective sequential functionalization. Copyright
- Tang, Dan-Tam D.,Collins, Karl D.,Ernst, Johannes B.,Glorius, Frank
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supporting information
p. 1809 - 1813
(2014/03/21)
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- Novel Process for the Preparation of Nitrogen Substituted Aminotetralins Derivatives
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The present invention provides an alternative synthesis of N-substituted aminotetralines comprising resolution of N-substituted aminotetralins of formula (II), wherein R1, R2 and R3 are as defined for compound of formula (I).
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Paragraph 0254-0255
(2013/05/08)
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- Alkylboronic esters from copper-catalyzed borylation of primary and secondary alkyl halides and pseudohalides
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Easy access: An unprecedented copper-catalyzed cross-coupling reaction of the title compounds with diboron reagents is described (see scheme; Ts=4-toluenesulfonyl). This reaction can be used to prepare both primary and secondary alkylboronic esters having diverse structures and functional groups. The resulting products would be difficult to access by other means. Copyright
- Yang, Chu-Ting,Zhang, Zhen-Qi,Tajuddin, Hazmi,Wu, Chen-Cheng,Liang, Jun,Liu, Jing-Hui,Fu, Yao,Czyzewska, Maria,Steel, Patrick G.,Marder, Todd B.,Liu, Lei
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supporting information; experimental part
p. 528 - 532
(2012/02/04)
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- NOVEL PROCESS FOR THE PREPARATION OF NITROGEN SUBSTITUTED AMINOTETRALINS DERIVATIVES
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The present invention provides an alternative synthesis of N-substituted aminotetralines comprising resolution of N-substituted aminotetralins of formula (II), wherein R1, R2 and R3 are as defined for compound of formula (I).
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Page/Page column 36
(2012/01/13)
-
- PROCESSES FOR PREPARING HIGHLY PURE ROTIGOTINE OR A PHARMACEUTICALLY ACCEPTABLE SALT THEREOF
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Provided herein are convenient, industrially advantageous and environmentally friendly processes for the preparation of (?)-(S)-5-hydroxy-2-[N-n-propyl-N-2-(2-thienyl)ethylamino]tetralin (rotigotine) or a pharmaceutically acceptable salt thereof. Provided further herein is a highly pure rotigotine or a pharmaceutically acceptable salt thereof substantially free of impurities, processes for the preparation thereof, and pharmaceutical compositions comprising highly pure rotigotine or a pharmaceutically acceptable salt thereof substantially free of impurities.
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Page/Page column 11
(2012/01/13)
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- Chemo-enzymatic approach to the synthesis of the antithrombotic clopidogrel
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The (S)-2-chlorophenylglycine moiety is well recognized in the structure of (S)-clopidogrel, a known antithrombotic drug. We prepared an enantiomerically pure chiral building block via an enzyme-catalyzed resolution of (RS)-N-Boc-2-chlorophenylglycine methylester. The best results were obtained by means of an immobilized subtilisin, the cross-linked enzyme aggregate (Alcalase-CLEA). The high enantiomeric excess of the synthon obtained remained the same over the course of clopidogrel synthesis; the simplicity of the process makes this pathway suitable for large-scale preparation.
- Ferraboschi, Patrizia,Mieri, Maria De,Galimberti, Fiorella
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experimental part
p. 2136 - 2141
(2010/10/03)
-
- PROCESSES FOR PREPARING HIGHLY PURE ROTIGOTINE OR A PHARMACEUTICALLY ACCEPTABLE SALT THEREOF
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Provided herein are convenient, industrially advantageous and environmentally friendly processes for the preparation of (-)-(S)-5-hydroxy-2-[N-n-propyl-N-2-(2-thienyl)ethylamino] tetralin (rotigotine) or a pharmaceutically acceptable salt thereof. Provided further herein is a highly pure rotigotine or a pharmaceutically acceptable salt thereof substantially free of impurities, processes for the preparation thereof, and pharmaceutical compositions comprising highly pure rotigotine or a pharmaceutically acceptable salt thereof substantially free of impurities.
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Page/Page column 26
(2010/07/09)
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- PROCESS FOR PREPARING CLOPIDOGREL
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A process for preparing clopidogrel or a salt thereof.
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Page/Page column 5
(2008/06/13)
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- Phenyl substituted dipeptide amides
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The invention relates to novel substituted tyrosyl alanine dipeptide amides of the formula: STR1 and the pharmaceutically acceptable acid addition salts thereof wherein R1 is hydrogen, lower alkyl, hydroxy, --OCO2 lower alkyl, lower alkoxy, --O(CH2)n -phenyl with the phenyl optionally substituted by halogen, --NO2, --CN, --NH2 or lower alkyl wherein n is 1 to 4; R2 and R3 represent lower alkyl, halogen, or lower alkoxy, or either one of R2 or R3 is hydrogen and the other is lower alkyl, lower alkoxy or halogen; R4, R5, R6, R7, R8, and R9 may be the same or different and represent hydrogen or lower alkyl; R10 is selected from the group consisting of where ALK represents alkylene, thioalkylene, oxyalkylene, having 1 to 5 carbon atoms; alkenylene and alkynylene having 2 to 4 carbon atoms; and X represents pyridyl, pyrimidinyl, 9H-fluoren-9-yl, diphenylmethyl, thienyl, carboxy, lower alkoxy carbonyl, substituted phenyl wherein the phenyl substituent is amino, hydroxy, halogen, nitro, methylenedioxy, lower alkyl, carboxy, lower alkoxycarbonyl, lower alkoxy, carboxamide, diloweralkylamino or X represents phenyl, when ALK is not alkylene; or R10 is STR2 where p and q are independently 1 to 4; or R9 and R10 together with N is STR3 where r and t are independently 1 to 4; v represents an asymmetric carbon that may be racemic or have the D or L configuration; w represents an asymmetric carbon when R7 and R8 are not the same that may be racemic or have the D or L configuration. These compounds are useful as analgesic and/or antihypertensive compounds.
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- Carbon-13 nuclear magnetic resonance spectra of fentanyl analogs
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Natural abundance carbon-13 chemical shifts are reported for the hydrochloride salts of fentanyl and fifteen analogs. The signals are assigned on the basis of chemical shift theory, SFORD multiplicities, signal intensities, comparisons with model compounds, and thiophene carbon-proton coupling constants. In addition to its forensic value, the data suggest that the solution conformations of the analogs are similar to that of fentanyl hydrochloride.
- Brine,Boldt,Huang,Sawyer,Carroll
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p. 677 - 686
(2007/10/02)
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- Lewis-acid Promoted Aromatic Cyclization of &α-Chlorosulfides: Synthesis of Ethyl Isothiochroman-1-carboxylate and Related Compounds
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A variety of ethyl isothiochroman-1-carboxylates and related compounds were synthesized by treatment of 2-chloro-2-acetates with stannic chloride in methylene chloride.The same procedure was applied to the synthesis of ethyl 4-chloro-4-methyltetrahydrothiopyran-2-carboxylate.Some isothiochroman-1-carboxylic acids were prepared and evaluated for antiinflammatory activity.Among the compounds tested, 7-phenoxyisothiochroman-1-carboxylic acid showed weak activity.
- Ishibashi, Hiroyuki,Okada, Motofumi,Iida, Kyoko,Ikeda, Masazumi
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p. 1527 - 1529
(2007/10/02)
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- 5-Halo-pyrimidin-2-ones, the salts thereof
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Compounds of the formula: STR1 wherein X represents a halogen atom; R1 and R2, which may be same or different, each represents a hydrogen atom, or a C1-4 alkyl group; Het represents a C-attached 3-9 membered, saturated, unsaturated or aromatic heterocyclic ring containing one or more hetero atoms selected from O, N and S and optionally carrying a fused ring and/or optionally substituted by one or more substituents selected from halogen atoms and hydroxy, C1-4 alkoxy, amino, acylamino, nitro, oxo, C1-4 alkyl groups and monocyclic carbocyclic and heterocyclic aryl groups having 5 to 8 ring members; such a heterocyclic ring being saturated and having only a single heteroatom when there are 3 or 4 ring members; and alk represents a C1-4 saturated or unsaturated, straight or branched chain, divalent aliphatic hydrocarbyl group optionally substituted by one or more groups selected from carbocyclic aryl groups and heterocyclic groups as defined for Het above, and the salts thereof have been found to possess metaphase arresting ability which by virtue of its reversibility is of use in combating abnormal cell proliferation. Thus a knowledge of the cell division cycles of the normal and abnormal cells enables a cytotoxic drug to be administered while the abnormal cells are in a phase susceptible to attack and while the normal cells are in a non-susceptible phase. The compounds of the invention are prepared by alkylation, ring closure of the pyrimidine ring, halogenation or ring closure of the heterocyclic ring Het.
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